RE: starship-design: Re: Aliens, why haven't they contact us?

["L. Parker" <lparker@cacaphony.net>]

-----Original Message-----
From:	jimaclem@juno.com [SMTP:jimaclem@juno.com]
Sent:	Friday, July 18, 1997 8:18 AM
To:	KellySt@aol.com
Cc:	TLG.van.der.Linden@tip.nl; starship-design@lists.uoregon.edu
Subject:	starship-design: Re: Aliens, why haven't they contact us?

Just a thought to consider folks.  All living organisms on this planet,
including viruses have DNA and RNA constructed from the same four
proteins, adenine, cytosine, guanine and tyrosine.  (And I do mean ALL
life forms on this planet, from viruses to trees to us).  The chances
that an alien microbe, or anything else, would use these same proteins
seem rather small, thus rendering them and us relatively harmless to each
other since we cant read each other's cellular codes.


Jim,

Sorry, but that reasoning won't wash. Using the ecology of THIS planet as a basis for the behavior of organisms from another ecology is like trying to determine what color light is with a yard stick - you can describe the color in terms that are producible with a yard stick, but you can't measure light with the yard stick.

While it is certainly possible or even likely that non-terrestrial organisms which are based upon different proteins would find it difficult or impossible to infect a terrestrial host, that does NOT mean that they couldn't KILL a terrestrial organism. The infectious attempt itself may kill both organisms. From the point of vew of the victim it really doesn't matter. Dead is still dead.

I also think that it is likely that non terrestrial organisms WILL be based on the same proteins, they have been found in interstellar dust clouds using spectroscopic analysis. There is therefore a significant chance that there will be RNA/DNA based life out there which WILL find us tasty.

L. Parker

                                                          (o o)
------------------------------------------------------oOO--(_)--OOo---------
Long experience has taught me not to believe in the limitations indicated by 
purely theoretical considerations. These - as we well know - are based on 
insufficient knowledge of all the relevant factors." 

Guglielmo Marconi